Liquid crystal displays are passive display devices. To display color images, a color filter needs to be provided. Referring to FIG. 4, a first kind of typical color filter 1 defines a plurality of pixels formed by arranging red (R), green (G), and blue (B) sub-pixels in a matrix. Each pixel includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The structure of the color filter 1 is simple. However, in each of areas such as that shown within rectangular area I in FIG. 4, there is only one kind of sub-pixel. The area within rectangular area I has the same size as each of the pixels. Therefore, the capability of fine color mixing is poor, and a liquid crystal display using the color filter 1 tends to display poor quality color images.
Referring to FIG. 5, a second kind of typical color filter 2 includes a plurality of red (R), green (G), and blue (B) sub-pixels. The red, green and blue sub-pixels are arranged such that their centers define a regular, repeating array of equilateral triangles. Each of areas such as that shown within rectangular area II in FIG. 5 has a same size as the area within rectangular area I of the color filter 1. However, there are three kinds of sub-pixels in the area within rectangular area II. Accordingly, the quality of color images displayed by a liquid crystal display using the color filter 2 is better than that of the liquid crystal display using the color filter
Referring to FIG. 6, part of a driving circuit of the liquid crystal display using the color filter 2 is shown. The driving circuit includes a plurality of gate lines 11 being parallel to each other, and a plurality of signal lines 12. The gate lines 11 are connected to gate electrodes of corresponding thin film transistors, and are driven by a driving integrated circuit (IC) 13. Each signal line 12 is connected to source electrodes of thin film transistors according to the same color sub-pixels, and is driven by a driver 14. Therefore the distribution of the signal lines 12 is complex, and the signal lines 12 are always configured with right-angled bends. However, disruption or cutoffs may easily occur at the right-angled bends of the signal lines 12. This tends to result in a low yield rate in mass production of the color filter 2.
Referring to FIG. 7, a third kind of typical color filter 3 includes a plurality of red (R), green (G), and blue (B) sub-pixels arranged in a regular, repeating mosaic. Each of areas such as that shown within rectangular area III in FIG. 5 has a same size as the area within rectangular area I of the color filter 1. However, there are three kinds of sub-pixels in the area within rectangular area III. Accordingly, the quality of color images displayed by a liquid crystal display using the color filter 3 is better than that of the liquid crystal display using the color filter 1.
Referring to FIG. 8, part of a driving circuit of the liquid crystal display using the color filter 3 is shown. Signal lines 15r, 15g, 15b are respectively connected to corresponding thin film transistors according to red, green, and blue sub-pixels. Therefore the distribution of the signal lines 15r, 15g, 15b is complex, and the signal lines 15r, 15g, 15b are always configured with right-angled bends. However, disruption or cutoffs may easily occur at the right-angled bends of the signal lines 15r, 15g, 15b. This tends to result in a low yield rate in mass production of the color filter 3.
What is needed is a color filter which can overcome the above-described problems.